JP4560235B2 - Angle adjustment table device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention is applied to various machine devices such as various robots, semiconductor manufacturing devices, precision machines, machine tools, etc., and an angle adjustment table device capable of rotationally positioning an object such as a workpiece mounted on a table at a minute angle. About.
[0002]
[Prior art]
Conventionally, a linear motion guide unit shown in FIG. 7 is known. The linear motion rolling guide unit 40 includes a track rail 41 and a slider 42 placed in a state of being laid over the track rail 41. Track grooves 49 are formed on both side surfaces of the track rail 41 in the longitudinal direction, and the slider 42 is slidable on the track rail 41 via rolling elements 46 rolling on the track grooves 49. A bolt is inserted into a mounting hole formed on the track rail 41 so as to open on the upper surface in the longitudinal direction of the track rail 41, and the bolt is formed on a mounting base such as a bed, a machine base, a processing table or the like. The track rail 41 is fixed to the mounting base by screwing into the hole. The slider 42 has a casing 43 that can move relative to the track rail 41, and end caps 44 that are attached to both ends of the casing 43. In the upper part of the casing 43, mounting holes for mounting other devices, machine parts, chucks, gripping devices and the like are formed.
[0003]
Recesses are formed on the lower surfaces of the casing 43 and the end cap 44 so that the casing 43 and the end cap 44 move across the track rail 41. Track grooves 50 are formed in the recesses at positions facing the track grooves 49 of the track rail 41. A rolling element 46 such as a ball incorporated in the casing 43 rolls on a load raceway composed of opposed raceway grooves 49 and 50. In order to prevent the rolling elements 46 from falling off the casing 43, a holding band 47 is attached to the casing 43 so as to surround a large number of rolling elements 46. In the end cap 44, the claws scooping the rolling elements 46 from the raceway grooves 49 of the track rails 41 and the rolling elements 46 are turned in order to circulate the rolling elements 46 corresponding to both side surfaces of the track rails 41 in the longitudinal direction. A turning path is formed.
[0004]
The end cap 44 is attached with an end seal 45 that achieves a seal between the track rail 41 and both ends of the slider 42 in the longitudinal direction. The end caps 44 are attached to both end faces of the casing 43 with attachment screws or the like that are passed through a plurality of attachment holes. In the linear motion rolling guide unit, a load raceway composed of raceway grooves 49, 50, a direction change path formed in the end cap 44, and a return hole formed in the casing 43 in parallel with the raceway groove 50. 51 constitutes an infinite circuit for the rolling elements 46. Even when the rolling element 46 is loaded on the track, the rolling element 46 rolls in contact with the raceway grooves 49 and 50 so that the slider 42 smoothly moves with respect to the track rail 41. It can move relative. In the linear motion guide unit, grease or lubricating oil is generally used as a lubricant for lubricating the rolling path, and the grease is supplied to the rolling path of the rolling element 46 through the grease nipple 48.
[0005]
Further, a rotary table device as shown in FIG. 8 is known. The rotary table device is a direct drive type servo actuator directly connected to the motor 60, and is configured to be capable of high-speed and high-precision positioning in the rotational direction without backlash or lost motion. A servo actuator that rotates and positions the table 52 includes a motor 60, an optical encoder 59, and a rotation bearing 55. The motor 60 includes a rotor 54 attached to the table 52 and a stator 53 attached to the housing 61. In the rotary table device, the table 52 is rotatably arranged in a housing 61 via a rotation bearing 55 including an inner ring 56, an outer ring 57, and a cylindrical roller 58 that is a rolling element. The rotation bearing 55 has a structure in which rollers 58 are alternately arranged in the circumferential direction with their axes intersecting each other, and is composed of a cross roller bearing that can load loads in all directions by one. Yes.
[0006]
Japanese Patent Laid-Open No. 2000-238232 discloses a θ-axis adjusting mechanism for a work mounting table. The θ-axis adjusting mechanism is configured such that a protruding piece standing up from a nut is sandwiched from both sides by a cam follower disposed on a bracket arm protruding from a table. A ball screw that is rotated by a drive motor and an axis line by rotation of the ball screw. A linear motion unit comprising a screwing nut that moves along the screw and a protruding piece standing up from the screwing nut is arranged on the side portion of the work placement table, and the roller-like unit that holds the protruding piece from both sides and supports it. Equipped with a bearing that rotatably supports the cam follower with a bracket arm that protrudes from the work placement table. The θ-axis adjustment mechanism is assembled so that the work placement table can be rotated and adjusted in the θ direction via the bracket arm by the cam follower being driven by a protruding piece that moves along the axis of the ball screw by the operation of the linear motion unit. Is.
[0007]
Japanese Utility Model Laid-Open No. 4-133540 discloses a moving table. The moving table is provided with a thrust bearing between the base and the stage, and the stage is freely positioned by driving the stage with each driving device. The stage is placed on the upper surface of the base via the thrust bearing. The drive is connected to the side of the stage. An orthogonal linear guide is provided on the upper surface of the base and the side of the stage, and a slide member is connected to both linear guides via a hinge shaft. When the stage is moved, the slide member slides or bends to follow the movement of the stage, preventing the stage from rising and tilting with respect to the eccentric load.
[0008]
[Problems to be solved by the invention]
However, in the rotary table device as shown in FIG. 8, the rotor 54 constituting the motor 60 is provided over the entire circumference of the table 52, and the stator 53 corresponding to the rotor 54 extends over the entire circumference in the annular groove of the housing 61. Since the motor 60 itself is provided, the height of the motor 60 itself is increased, the size thereof is increased, and the structure itself is complicated.
[0009]
In the conventional θ-axis adjusting mechanism, when the angle changes, the cam followers on both sides are in a state of being sandwiched obliquely with respect to the protruding piece and become unstable, so high-precision angle adjustment cannot be expected. In addition, since the structure is pressed by a compression spring, if it moves away from the center position, the pinching force increases, and smooth movement cannot be expected.
[0010]
Further, the above moving table is complicated because each drive device must be driven and set in position. In addition, it is necessary to prevent the stage from being lifted by the linear guide.
[0011]
It is obvious that the above-described conventional apparatus is configured to have a large cross-sectional height of the apparatus itself, the structure is also configured to be complicated, and the manufacturing cost is high. For example, there are a wide variety of semiconductor-related manufacturing apparatuses in recent years, and semiconductor manufacturing apparatuses, image processing inspection apparatuses, and the like are increasingly demanding highly accurate, compact, and inexpensive positioning apparatuses. Therefore, as an angle adjustment table device, it is possible to perform angular positioning drive in the rotational direction, that is, the θ direction, and to reduce the number of parts, how to reduce the size of the device itself, reduce the weight, and improve the response. There is.
[0012]
[Means for Solving the Problems]
The object of the present invention is to solve the above-mentioned problems, and can be applied to various devices such as semiconductor manufacturing equipment, precision measuring instruments with image processing, inspection machines, assembling machines, etc., and an object such as a workpiece is mounted on a table. In addition, it is possible to rotate and position an object such as a workpiece with high precision at a minute angle, reduce the number of parts of the device itself, reduce the height dimension, make the device compact, and achieve high response of positioning adjustment. It is to provide an angle adjustment table device excellent in the above.
[0013]
This invention is a rectangular thick plate-shaped bed, first becomes a circular which is rotatably supported via the cross low labeling a bearing table to the bed, the plate which protrudes from a portion of the outer peripheral portion of said table And a drive device disposed on a side surface of one side of the bed for rotating the table through a small angle through the arm,
The driving device includes a motor provided on a motor bracket fixed to the side surface of the bed , one end connected to a rotation shaft of the motor, and the other end extending along the longitudinal direction of the side surface of the bed. ball screw shaft rotatably supported anchored end bracket through a third bearing to the side of the bed opposite the motor bracket, the rotation of the screwed with the ball screw shaft and the ball screw shaft with the ball screw nut to move along the ball screw shaft, and the motor bracket and the longitudinal direction along one secured first track rail on the side of the bed between said end brackets the the first linear motion guide unit comprising a first slider of one which is movable through a ball rolling elements along a first track rail, is fixed to the first slider And the moving base ball screw nut is fixed, and a connecting device for connecting the can to the moving base transmission and the arm linear movement of the moving base by rotation of the motor to the angular rotation movement of the arm Consist
The coupling device includes a rotary base constituted by a rotary shaft rotatably supported via a plurality of angular contact bearings which are second bearings disposed on the movable base, and a lower part of the arm, Comprising a second linear motion guide unit for connecting the turntable and the arm so as to be linearly movable;
The second linear motion guide unit includes one second track rail which is fixed to the upper surface of the turntable so as to extend in the direction of the rotation center of the table, and a ball of a rolling element along the second track rail. It consists a movable and is and second sliders one fixed to the lower surface of the arm, about the angular adjustment table apparatus that is configured.
[0014]
In this angle adjustment table device, since the first bearing is constituted by a cross roller bearing, the angular movement of the table with respect to the bed, that is, the displacement of a minute angle is smoothly performed with high accuracy. Angular positioning can be achieved. In this angle adjustment table device, the rotational motion by the second bearing, the linear motion in the table tangential direction by the first linear motion guide unit, and the linear motion in the table rotational center direction by the second linear motion guide unit are: There is no backlash and it is transmitted smoothly, creating a highly accurate motion transmission system.
[0015]
Since the angle adjusting table device is configured as described above, displacement in the table tangential direction by the screw device generated by driving the motor causes the first linear motion guide unit, the second bearing, and the second bearing to move. This is transmitted as a displacement in the rotational direction of the table by the linear motion guide unit. Therefore, this angle adjustment table device can provide a small angle table suitable for fine angle positioning, that is, alignment, in particular, positioning in the angle direction (θ direction) consisting of a minute rotation direction. Therefore, the rotary table device as shown in Fig. 8 can solve the problem of high height, and can be constructed in a thin structure, providing a highly accurate, compact, and inexpensive device. Thus, a thin and highly accurate XY-θ table device can be configured even if it is mounted on an XY table that is a positioning device that moves.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of an angle adjustment table device according to the present invention will be described below with reference to the drawings. This angle adjustment table device can be applied to various robots, semiconductor manufacturing devices, precision machines, machine tools, precision measuring instruments with image processing, inspection machines, assembly machines, and other various mechanical devices.
[0017]
As shown in FIGS. 1 to 3, this angle adjustment table device is generally rotatably supported through a cross roller bearing 15 constituting a first bearing in the center of a bed 1 and a bed 1 that are rectangular thick plates. It is composed of a circular table 2, a plate-like arm 4 projecting from a part of the outer peripheral portion 39 of the table 2, and a driving device 3 for rotating the table 2 by a small angle via the arm 4. . Specifically, as shown in FIGS. 1 to 5, the driving device 3 is disposed on a side surface 36 on one side of the bed 1 that is also tangential to the table 2. The drive device 3 includes devices such as a power supply device, a driver, and a control (not shown).
[0018]
As shown in FIG. 1, a see-through hole 31 is provided in the center of the table 2, and the see-through hole 31 penetrates the bed 1 as well. The driving device 3 is disposed on the side surface 36 of the bed 1, and thus is disposed on a part of the table 2 in the circumferential direction corresponding to the side surface 36 of the bed 1. The bed 1 is formed from a substantially rectangular thick plate, and the table 2 is formed in a circular shape. A square 33 of the bed 1 is formed with a mounting hole 33 for fixing to a mounting body such as a base and an XY table device, and a mounting screw hole for mounting an object such as a workpiece on the upper surface of the table 2. 32 is formed.
[0019]
As shown in FIG. 3, the rectangular thick plate-like bed 1 is formed with a large circular hole 37 at the center for mounting the table 2 rotatably. An outer ring 17 that forms the cross roller bearing 15 is attached to the hole 37 of the bed 1. The inner ring 16 of the cross roller bearing 15 is fitted on the outer peripheral surface of the boss portion 38 of the table 2 formed in a circular shape, and the table 2 is rotatably supported by the bed 1 via the cross roller bearing 15. Yes. The cross roller bearing 15 includes rollers 18 arranged in the circumferential direction with their axis centers alternately intersected between an inner ring 16 fixed to the table 2 and an outer ring 17 fixed to the bed 1. . The table 2 can receive loads in the vertical direction, the horizontal direction, and the moment direction with respect to the bed 1 via the cross roller bearing 15.
[0020]
The driving device 3 includes a motor 8 provided on the motor bracket 14 fixed to the side surface 36 of the bed 1, a screw shaft 11 connected to the rotary shaft 62 of the motor 8 and extending along the longitudinal direction of the side surface 36, and the screw shaft 11. And the first track rail 21 and the first track rail 21 disposed along the longitudinal direction of the side surface 36 of the bed 1 and the nut 12 that moves along the screw shaft 11 as the screw shaft 11 rotates. The first linear motion guide unit 6 comprising a first slider 23 that is movable along the first slider 23, the movable table 5 fixed to the first slider 23 and the nut 12 fixed thereto, and the movable table 5 and the arm 4 are rotatable and linear. It is comprised from the connection apparatus 35 couple | bonded so that a movement is possible. The driving device 3 is covered with a cover 9 except for the motor 8 attached to the motor bracket 14.
[0021]
In the driving device 3, the rotating shaft 62 of the motor 8 is connected to one end of the screw shaft 11 by a coupling 34. The other end of the screw shaft 11 is rotatably supported by an end bracket 19 that is fixed to the side surface 36 of the bed 1 so as to face the motor bracket 14 via a bearing 63 (third bearing). The first track rail 21 constituting the first linear motion guide unit 6 is disposed between the motor bracket 14 and the end bracket 19 along the longitudinal direction of the side surface 36 of the bed 1. As shown in FIG. 3, the moving base 5 is fitted with a screw shaft 11 and fixedly supported by the first slider 23, and the nut 12 is fixed. The turntable 25 is disposed below the arm 4, and includes a rotating shaft 13 that is rotatably supported by the moving table 5 via a bearing 30.
[0022]
The coupling device 35 includes a rotating table 25 constituted by a rotating shaft 13 rotatably supported by a moving table 5 via a bearing 30 (second bearing), and the rotating table 25 and the arm 4 as the table 2 rotates. The table 2 is composed of a second linear motion guide unit 7 connected so as to be movable in the direction of the rotation center O of the table 2. In other words, the second linear motion guide unit 7 has a function of connecting the turntable 25 and the arm 4 so as to be relatively movable. As shown in FIGS. 4 and 5, the second linear motion guide unit 7 includes a second track rail 22 that is fixed to the upper surface of the turntable 25 so as to extend in the direction of the center of rotation of the table 2, and a second track rail 22. The second slider 24 is movable along the direction of the rotation center O of the table 2 and is fixed to the lower surface of the arm 4. Specifically, as shown in FIG. 4, the second linear motion guide unit 7 includes a second track rail 22 fixed to a concave groove 64 formed on the upper surface of the turntable 25, and the second track rail 22. and saddled slidably I along the and a second slider 24 which is fixed to the recessed groove 65 formed in the direction of the rotational center O of the table 2 to the lower surface of the arm 4.
[0023]
The end (other end) opposite to the motor 8 of the screw shaft 11 is rotated through a bearing 63 (third bearing) on an end bracket 19 fixed to the side surface 36 of the bed 1 so as to face the motor bracket 14. It is supported freely.
[0024]
A disk-shaped origin mark 29 is provided at the other end of the screw shaft 11, and an origin sensor 20 for detecting the origin mark 29 corresponding to the origin mark 29 is provided at a portion facing the end bracket 19. The origin position is detected. Further, limit sensors 26 are provided on the side surfaces 36 of the bed 1 in the vicinity of both ends of the first track rail 21, respectively. The limit sensor 26 senses a limit plate provided on the moving table 5 and detects the moving plate 5. Overrun is prevented.
[0025]
In this angle adjustment table device, the first linear motion guide unit 6, the second linear motion guide unit 7, the screw device 10 including the screw shaft 11 and the nut 12, and the rotary shaft 13 constituting the rotary base 25 are supported. Although not shown in the drawings, the rolling elements made up of a plurality of balls are interposed in the bearing 30. In this angle adjustment table device, the first linear motion guide unit 6 and the second linear motion guide unit 7 roll between the track grooves of the first track rail 21 and the first slider 23 as shown in FIG. It is a linear motion rolling guide unit that incorporates balls and slides smoothly without any play. The screw shaft 11 constitutes a ball screw shaft, the nut 12 constitutes a ball screw nut, and the screw shaft 11 and the nut 12 constitute a screw device 10 for the ball screw. The screw device 10 has a structure in which a ball is incorporated between the screw shaft 11 and the nut 12 and smoothly rotates and slides without play. The bearing 30 is composed of a plurality of angular contact bearings that support the rotary table 25 on the movable table 5 and is configured to be smoothly rotated without play.
[0026]
This angle adjustment table device is configured as described above and operates as follows. As shown in FIG. 6, the angle adjusting table device is configured such that when the motor 8 is operated and the screw shaft 11 is rotationally driven to displace the table 2 to an arbitrary angle α with respect to the bed 1, the screw shaft 11 is rotated. 11 is guided by the first linear motion guide unit 6 disposed in the longitudinal direction of the side surface 36 of the bed 1 and moves linearly. Therefore, the arm 4 coupled to the movable table 5 moves together to rotate the table 2 by a small angle. For the linear movement of the movable table 5, the rotary table 25 and the second linear motion guide unit 7 are operated in order to guide the angular rotation of the table 2. As shown in FIG. 6, the operation of the rotary table 25 and the second linear motion guide unit 7 is as follows. If the point on the arm 4 of the table 2 is moved to an arbitrary angular position α with MO as the initial point, the linear movement distance S Since the point becomes MS and the point MO moves to the point M1 on the arc, the first point disposed on the lower surface of the arm 4 is used to correct the distance δ between the point MS and the point M1. 2 Since the linear motion guide unit 7 slides and the point MS becomes an angle (α), the turntable 25 rotates by a minute angle. That is, the track rail 22 of the second linear motion guide unit 7 always rotates so as to face the rotation center O of the table 2. The operations of the second linear motion guide unit 7 and the turntable 25 are performed simultaneously.
[0027]
【The invention's effect】
Since the angle adjustment table device according to the present invention is configured as described above, the angle adjustment table device linearly moves in the direction of the center of rotation of the first linear motion guide unit having the first slider that linearly moves in one direction of the side surface of the bed. It incorporates a second linear motion guide unit with a second slider. The table can be rotated via a ball screw screw device, and the device itself can be configured in a simple, compact, highly accurate and responsive manner. A positioning apparatus that can adjust the position of a fine minute angle can be configured at low cost. Therefore, when this angle adjustment table device is mounted on an XY table, it can constitute a thin and highly accurate XY-θ table. This is preferable when applied to various mechanical devices such as inspection machines and assembly machines.
[Brief description of the drawings]
FIG. 1 is a perspective view showing an embodiment of an angle adjustment table device according to the present invention.
2 is a plan view showing an upper surface portion of the angle adjustment table device of FIG. 1 with a cover removed from a driving device.
3 is a cross-sectional view showing a II cross section in the angle adjustment table device of FIG. 2;
4 is a side view showing a right side surface portion obtained by removing a cover from the drive device in the angle adjustment table device of FIG. 2; FIG.
5 is a plan view showing a state in which an arm portion of a table and a cover of a driving device are removed from the angle adjustment table device of FIG. 2. FIG.
FIG. 6 is an explanatory diagram showing an adjustment amount due to a change in the angle of the table by driving the driving device in the angle adjustment table device.
FIG. 7 is a perspective view showing a state in which a part of the linear motion guide unit incorporated in the drive device in the angle adjustment table device is broken.
FIG. 8 is a perspective view showing a state in which a part of a conventional rotary table device is broken.
[Explanation of symbols]
1 bed 2 table 3 driving device 4 arm 5 moving table 6 first linear motion guide unit 7 second linear motion guide unit 8 motor 9 cover 10 screw device (ball screw)
11 Screw shaft 12 Nut 13 Rotating shaft 14 Motor bracket 15 Cross roller bearing (first bearing)
16 Inner ring 17 Outer ring 18 Roller 19 End bracket 20 Origin sensor 21 First track rail 22 Second track rail 23 First slider 24 Second slider 25 Turntable 26 Limit sensor 29 Origin mark 30 Bearing (second bearing)
31 hole 34 coupling 35 coupling device 36 side surface 37 mounting hole 38 mounting boss part 39 outer peripheral part 62 motor rotating shaft 63 bearing (third bearing)

Claims (1)

Rectangular thick plate-shaped bed, first becomes a circular which is rotatably supported via the cross low labeling a bearing table to the bed, plate-shaped arm which protrudes from a portion of the outer peripheral portion of said table, and A driving device disposed on a side surface of one side of the bed for rotating the table by a minute angle through the arm;
The driving device includes a motor provided on a motor bracket fixed to the side surface of the bed , one end connected to a rotation shaft of the motor, and the other end extending along the longitudinal direction of the side surface of the bed. ball screw shaft rotatably supported anchored end bracket through a third bearing to the side of the bed opposite the motor bracket, the rotation of the screwed with the ball screw shaft and the ball screw shaft with the ball screw nut to move along the ball screw shaft, and the motor bracket and the longitudinal direction along one secured first track rail on the side of the bed between said end brackets the the first linear motion guide unit comprising a first slider of one which is movable through a ball rolling elements along a first track rail, is fixed to the first slider And the moving base ball screw nut is fixed, and a connecting device for connecting the can to the moving base transmission and the arm linear movement of the moving base by rotation of the motor to the angular rotation movement of the arm Consist
The coupling device includes a rotary base constituted by a rotary shaft rotatably supported via a plurality of angular contact bearings which are second bearings disposed on the movable base, and a lower part of the arm, Comprising a second linear motion guide unit for connecting the turntable and the arm so as to be linearly movable;
The second linear motion guide unit includes one second track rail which is fixed to the upper surface of the turntable so as to extend in the direction of the rotation center of the table, and a ball of a rolling element along the second track rail. It consists a movable and is and second sliders one fixed to the lower surface of the arm, the angular adjustment table apparatus that is configured.

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